Monday, December 21, 2009

Reconnecting the Grid in Potrero Hill

According to Curbed SF, the plans for replacing the Potrero Terrace-Annex housing projects on the Southeast side of Potrero Hill call for re-establishing the street grid on the hilly property.

The maps above compare the street grid as it was planned from the 19th century and the streets that exist today. The map on the left was made in 1907, but doesn't differ significantly from earlier maps. North-South streets were named for states, and East-West streets were named for the original counties of California (most changed to the numbers they currently bear when the Potrero Hill grid was merged into the existing grid of the Mission District in 1895. The weird little jogs many streets make as they cross Harrison show the boundary between these two almost-aligned grids).

While the 1907 map makes it look like a neat grid of streets had been laid down on Potrero Hill, the area shown was in fact largely undeveloped. Most of these streets 'existed' only in maps like the one above, and those that did exist were mostly unpaved.

The less-than-concrete nature of this grid made it susceptible to the changing whims of city planners. When the Potrero Terrace-Annex housing projects were built in the '40s, the streets were reconfigured according to the latest fashion.

60 years of history have shown that the winding, meandering roads that hugged the terrain did not foster a quiet bucolic atmosphere, but instead created indefensible spaces where outsiders didn't feel comfortable passing through. Combined with the area's geographical isolation, this street layout created a no-man's land into which even police didn't feel comfortable venturing.

For the last few years the city has been working with private developers to rebuild the Potrero Terrace-Annex housing projects and replace them with modern housing units under the HopeSF program. Apparently the latest plan goes beyond replacing the buildings and actually calls for recreating a grid of streets on the property:

Increasing the connectivity of the streets in this development is a great thing that will help reduce the auto-dependency of residents, increase the number of visitors to the area, and take pressure off of traffic bottlenecks on the few roads that pass all the way through this area.

The post above starts from the point of assuming that the existing housing projects will be torn down and replaced one way or another, because that is an inevitability.

We all (myself included) have opinions about how humanely government agencies treat the tenants of these projects and to what extent the projects goals are driven by profits for private developers.

But that's an argument to be taken up on another blog. The relevant point for me, and for this blog, was that the proposed redevelopment of this housing project will include a fundamental improvement to the street network of the area. Or rather, the correction of a bad mistake made 60+ years ago.

It's not the only problem facing the project, but this decision is a good one.

Under the plan, every unit of affordable housing will be replaced, and new affordable and market rate housing will be added. The people who now live in the projects will have to move out temporarily to other projects, or will be given housing vouchers, but they will return to new homes that are much nicer than the ones they left.

The problem isn't the street grid, streets that follow terrain are perfectly natural and can be found all around the world.

The problem is that they are projects. When you concentrate the poor in a place where nobody else has any reason to go, you get this type of situation.

I have public housing on my block, but it fits in with the character of the street, and it is only one building.

Just a few blocks away there is a public housing project that takes up the whole block. It's completely different from anything else around it, and has very little interaction with the surrounding neighborhood, and has the same issues (although not as extreme) as the Potrero projects. Both are on the typical SF street grid.

The difference between the two is that one is part of the surrounding neighborhood, and the other is concentrated and set apart from it's neighbors.

I'm glad to hear that there will be a combination of subsidized and market rate housing, I hope the design is in keeping with the surrounding areas, or at least is not depressing.

Your point is valid, the ultimate problem is that nobody except people who live in the Potrero terrace-Annex has a reason to go there. But a proximate cause for that problem is poorly-connected network of meandering streets.

Lack of pass-through traffic is an unavoidable side effect of such street networks, just ask anyone in Palo Alto or Diamond Heights.

Large developments (rich or poor) that take up an entire block can similarly divorce themselves from the community, and I'm opposed to those too.

But remember that this property is huge. It takes up several city blocks, and unless there are streets going through the property and out the other side, there is no hope of integrating it into the surrounding community.

It could still fail with a street grid, but I don't think it could succeed without one.

1) that land is spectacular. that developers want at it is no surprise to me. is it a surprise to you?

2) if that 'replacement' picture is accurate, why bother building new housing at all? replace military barracks with military barracks? what's the point?

as for the 'inevitability' of existing homes being torn down -- nonsense. there's no reason to clear the project out completely. there are lots of options for redevelopment -- not a single humane one includes kicking people out of their homes.

but it shouldn't matter what you or I think -- we should start by asking the residents what they want, and go from there. it's not rocket science. i know that has the potential to hurt developer profits, but life is hard sometimes.

is that really the strategy you're shooting for, Pedestrianist? cheerlead a tear-down so you can get a better street network, regardless the real-life consequences for actual human beings? what is the purpose of your blog if not to improve people's lives? or is it just white people's lives?